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1. Carbon is a non-metal. It belongs to the fourteenth group or IV A group in the
 modern periodic table. The elements of this group have four electrons in the valence shell.


2. Electronic configuration of carbon is 1S2 2S2 2P2.

3. Electro - negativity of carbon is 2.5.

4. Each carbon atom has four unpaired electrons when excited and tends to formfour covalent bonds.

5. The possibility of bonds formation by a carbon atom is as follows.

(i) Four Single covalent bonds, with atoms of same element like hydrogen, chlorine. 

(ii) Four Single covalent bonds with atoms of different elements.

(iii) carbon atoms may form one double bond and two Single bonds.

(iv) carbon atom may form one single bond and a triple bond.
Eg: __ C  C __ H or CH3 __ C  N
(v) carbon atoms may also form two double bonds as in CH2 = C = CH2

6. The concept of hybridisation was introduced by linus pauling (1931). The redistribution of orbitals of almost equal energy in individual atoms to give equal number of new orbitals with identical properties like energy and shape is called hybridisation.

7. The newly formed orbitals are called as hybrid orbitals.

8. The Process of combining of one S orbital and three P orbitals of an atoms to form four identical orbitals is called SP3 hybridisation. SP3 hybrid orbitals are oriented along four corners of tetrahedral and angle between any two orbitals is 109° 28'

9. In methane, carbon atom under goes SPhybridisation in the excited State. The four SP3 hybrid orbitals form four SP- S Sigma bonds between carbon and form hydrogen atoms.

10. The Shape of methane molecule is tetrahedral and its bond angle is 109° 28'.


11. In ethylene or ethene molecule, carbon atoms under go SP2 hybridisation in the excited state. Each carbon atom contains three SP2 hybrid orbitals and one unpaired P orbital.

12. In ethylene molecule, one SP2 orbital of one carbon atom over laps with the one SP2 orbital of the other carbon atom to form SP2 − SPSigma bond. The remaining two SPorbitals of each carbon atom get overlapped by S orbitals of two hydrogen atoms to form SP2 − S Sigma bonds. The unhybridised P orbitals on the two carbon overlap laterally to form a Π bond. So, a double bond is formed between two carbon atoms. The shape of ethylene molecule is planar triangular and its bond angle is 120°


13. The process of combining of one S orbital and one P orbital of an atom to form two identical orbitals is called SP hybridisation SP hybrid orbitals are oriented in the same plane and the angle between two orbitals is 180°

14. In acetylene or ethyne molecule, carbon atoms undergo Sp hybridisation in the excited state. Each carbon atom contains two Sp hybrid orbitals and two unpaired P orbitals.

15. In acetylene molecule on SP orbital of a carbon overlaps the SP orbital of other carbon atom to form SP − SP sigma bond. The other SP orbital of each carbon atom overlaps S orbitals of a hydrogen atom to form a sp − s sigma bond. The unhybridised P-orbitals of carbon atoms are laterally overlap with one another to form two Π bonds between two carbon atoms. So, a triple bond is formed between two carbon atoms. The shape of acetylene molecule is linear and its bond angle is 180°


16. The property of an element to exist in two or more physical forms having more or less similar chemical properties but different physical properties is called allotropy. Allotropes form due to the difference in the arrangement of atoms in the molecule

17. The allotropes of carbon are classified into two types. They are (i) Amorphous forms (ii) Crystalline forms.

18. Different amorphous allotropes of carbon are coal, coke, wood, charcoal, aninal charcoal, lamp black, gas carbon, petroleum coke, sugar charcoal etc.,

19. carbon in solid Phase can exist in three crystalline allotropic forms
       (i) Diamond     (ii) Graphite     (iii) Buckminster fullerence.


20. Diamond and graphite form covalent network structures when as buck minster follerence has a molecular solid with discrete C60 molecules.

21. In diamond each carbon atom undergoes Sp3 hybridisation in the excited state.

22. In graphite each carbon atom undergoes SP2 hybridisation in the excited state. Graphite forms a two dimensional layer structure with C − C bonds with in the layer, the layers are separated by a distance of 3.35A°

23. Fullerence C60 molecule contains 12 pentagonal and 20 hexagonal faces on its soccer ball shape and each Carbon atom undergoes SPHybridisation.

24. Nano tubes are another allotropic form of carbon discovered in 1991 by sumio Lijima

25. Nano tubes consist of hexagonal arrays of covalently bonded carbon atoms similar to the sheets in graphite. In nano tubes the sheet are rolled into cylinders.

26. Wohler produced an organic compound urea in the laboratory by heating an inorganic salt ammonium cyanate.

27. The phenomenon of linkage among atoms of the same element is called catenation. The highest catenation element is carbon due to its high c − c bond energy.

28. Carbon has the ability to form longest chains with its own atoms.

29. Carbno's ability
      (i) to form largest number of compounds
      (ii) to show catenation
      (iii) to form various types of bonds made it the verratile element.


30. The compounds containing only carbon and hydrogen in these molecules are called hydro carbons.

31. Hydrocarbons are classified into two types
      (i) Open chain hydrocarbons
      (ii) closed chain hydrocarbons


32. Hydrocarbons containing only single bonds between carbon atoms are called Alkanes.

33. Hydrocarbons containing atleast one double bond between carbon atoms are called Alkenes.

34. Hydrocarbons containing atleast one triple bond between carbon atoms are called Alkynes.

35. Hydro carbons containing only c - c single bonds are known as Saturated hydro carbons
e.g.: Allcanes.


36. Hydrocarbons that contain atleast one double bond or one triple bond between the two carbon atoms are called unsaturated hydrocarbons.
e.g.: Alkenes, Alkynes etc.,


37. A group of atoms in carbon compounds showing characteristic properties is called functional group.

38. Some functional groups and their formula 




      CnH2n+1 X (or) R − X

Halo hydrocarbons

   CH3C(Methyl chloride)

       R __ OH


   CH3OH (Methyl alcohol)

       R __ CHO


   CH3-CHO (Acetaldehyde)



       CH3 __ CO __ CH3
(Dimethyl Ketone)

        R __ COOH

  Carboxylic acids

      CH3 COOH (Acetic acid)

        R __ O __ R


         CH3 __ O __ CH3
        (Dinethyl Ether)

        R __ COOR


         CH3 COOCH3
       (Methyl acetate)

        R __ NH2

    primary amines

(Methyl amine)

        R __ NH__ R

   Secondary amines

         CH3 __ NH __ CH3
          (Dimethyl amine)


    Tertiary amines

       (Trimethyl amine)

39. The series of carbon compounds in which two successive compounds differ by - CH2 unit is called homologous series.
e.g.: CH4, C2H6, C3H8, ............


40. Homologous Series of organic compounds have following characteristic features
i) They have one general formula.
ii) Successive compounds in the series possess a difference of -CH2 unit
iii) They possess similar chemical properties due to the same functional group.
iv) They show a regular gradation in their physical properties.


41. The individual members of a homologous series are called homologs.

42. The general formula of alkanes is Cn H2n + 2
Examples: Methane - CH4
                      Ethane - C2H6
                      Propane - C3H8
                      Butane - C4H10
                      Pentane - C5H12

43. The general formula of alkenes is Cn H2n
Examples: Ethene - C2H4
                       propene - C3H6
                       Butene - C4H8
                       pentene - C5H10


44. The general formula of alkynes is Cn H2n − 2
Examples: Ethyne - C2H2
propyne - C3H4
                       Butyne - C4H6
                       pentyne - C5H8


45. The phenomenon of possessing same molecular formula but different properties by the compounds is known as isomerism. The compounds that exhibit isomerism are called isomers.

46. Isomerism is due to the difference in the structures is called structural isomerism.
       Eg: n-butane and Iso butane are structural isomers.


47. The IUPAC name of an organic compound consists of three parts:
       1) Word root                2) Prefix                 3) Suffix.


48. Word Root: The number of carbon atoms present in the molecules or principle chain is called word root.























49. prefix: The substituents in the molecule are shown in the prefix, prefix again has several parts known as primary prefix, secondary prefix, numerical prifix and number prefix

50. Primary prefix: It is useful only for cyclic compounds (cyclo)

51. Secondary Prefix: This tells about the second grade functional groups known as substituents.

52. Numerical Prefix: When the same substituent multiple bond or functional group is repeated twice, thrice etc.... are denoted by di, tri, tetra, .... respectively.

53. Number Prefix: This tells about to which carbon atoms of the compound the substituent (s), multiple bond (s) or functional group (s) are attached.

54. Suffix: The functional groups in the molecule are shown as the suffix. It also contains several parts known as primary suffix, secondary suffix, numerical suffix and number suffix etc.

55. Primary suffix: This tells about the saturation of the compound for saturated (c __ c) single bonded compounds it is 'ane'. For unsaturated (c = c) double bonded compounds. It is 'ene'. For unsaturated triple bonded (c 

 c) compounds. It is 'yne'.

56. Secondary Suffix: This tells about the functional groups with the particular term.

57. The following order is to be followed while naming carbon compound.
Numbers−numerical prefixes−secondary prefix−primary prefix−word root−numbers

 1                                    2                            3                         4                           5            6
−Numerical prefix,Primary suffix, number, numerical prefixes and secondary suffixes.

7                                           8                   9                           10                              11

58. suffixes and prefixes for some important characteristics functional groups

59. If there are more than one similar functional groups, 'e' letter of primary suffix may not be replaced.

60. Numbers are separated by comma (,) and numbers and designations by hyphen (-).

61. If you find more than one substituent in the structure you have to follow alphabetical order while naming them. For this numerical prefixes should not be considered.

62. The decreasing order of priority of functional groups.
- COOH > - COOR > - COX > - CHO > C = O > - OH > - NH2
> - OR > C = C > - C  C -


63. Numbering carbon atoms
(i) Numbering the carbon atoms from left to right or from right to left so that sum of the numbers indicating the positions of substituents and functional groups should be minimum.
(ii) the functional group carbon should be given the lowest number.
(iii) The carbon atoms of the chain terminating functional group say - CHO or
- COOH groups should be given always number '1'.

64. Longest Chain rule: Select the longest continuous chain of carbon atom which is known as parent chain or principle chain. All the other carbon atoms constitute in the chain are branched chains or side chains.


65. Lowest Number rule: The carbon compound which contains only one substituent number the carbon atom in such a way that the carbon atom carrying the substituent get the lowest number.

66. Lowest Sum rule: If there are two or more substituents in the carbon compounds the parent chain is numbered from the end which gives the lowest sum of more substituent carbon.


67. Alphabetical order: When two or more different groups are present, such groups are arranged in alphabetical order.

68. Nomenclature of carbon compounds

69. Writing the structures of the compound:
i) From the word root in the name, write the carbon atoms in the main chain.
ii) Numbering the carbon atoms in the chain from left to right or right to left.
iii) Attach the substituents at respective numbers of carbon atoms.
iv) Write the functional groups formula as per the name at the respective carbon atom.
v) Add required number of hydrogen atoms to each carbon atom to satisfy the tetravalency of each carbon atom.


70. Important reactions in organic compounds are
i) Combustion
ii) oxidation reactions
iii) Addition reactions
iv) Substitution reactions.


71. The process of burning of carbon or carbon compounds in excess of oxygen or air to give carbondioxide, heat and light is called combustion reaction.
e.g.: C + O2  CO2 + Energy
2 C2H6 + 7 O2   4 CO2 + 6 H2O + Energy

72. Generally, Saturated hydrocarbons burn with a clear light blue flame, where as unsaturated hydrocarbons burn with yellow flame with soot (carbon).

73. When coal, petroleum etc burn in air they give oxides of sulphur and nitrogen in addition of CO2 and H2O

74. Though combustion is generally oxidation reaction, all oxidation reactions are not combustion reactions.

75. Oxidation reactions may be carried out using oxidizing agents. Oxidizing agents or oxidants are substances that oxidize other Substances. They themselves under go reduction.

76. Ethyl alcohol undergoes oxidation with alkaline kMnO4 solution to form
acetaldehyde and finally acetic acid.

77. unsaturated organic compounds that contain multiple bonds (=,  bonds) like alkenes and alkynes undergo addition reactions to become saturated. During the reactions addition of the reagent takes place at the double bonded or triple bonded carbon atoms.


78. A catalyst is a Substance which increases or decreases the rate of a given reaction without itself finally undergoing any chemical change.

79. Areaction in which an atom or a group of atoms in a given compound is replaced by other atom or group of atoms is called a substitution reaction.

80. Methane (CH4) reacts with chlorine in the presence of Sunlight. Hydrogen atoms of CH4 are replaced by chlorine atoms.

81. Grains such as corn, wheat, barley are common sources for ethanol. Therefore, it is also called grain alcohol.

82. The process of conversion of starches and Sugars to Ethyl alcohol is called Fermentation process.

83. Pure ethanol is called absolute (100%) alcohol.

84. Denatured alcohol is ethanol that contains methanol, Methyl isobutyl ketone, aviation gasoline etc.

85. Denatured alcohol is toxic and 200 ml of it is a fatal dose to an adult.

86. Solution of about 10% ethanol in gasoline (gasohol) is a good motor fuel.

87. Ethyl alcohol is used in medicines such as tincture of iodine, cough Syrups and many tonics

88. Ethanoic acid is commonly call as acetioc acid. 5 - 8% solution of acetic acid in water is called vinegar and is used widely as a preservative in pickels.

89. The general formula of esters is R - COOR' where R and R' are alkyl groups.

90. The reaction between carboxylic acid and an alcohol in the presence of conc.H2SO4 to form sweet odoured substance, ester is called esterification.

91. Fats are esters of higher fatty acids and the trihydroxy alcohol known as glycerol.

92. Soap is a Sodium or potassium salt of a higher fatty acid like palmitic acid
(C15H3,COOH), Stearci acid (C17H35COOH), oleic acid (C17H33COOH) etc.


93. The formula of a soap in general is R COONa or RCOOK
(where R = C15H31; C17H35 etc)


94. Alkaline hydrolysis of triester of higher fatty acids producing soaps is called saponification.

95. Soaps are good cleansing agents.

96. A spherical aggoregrate of soap molecules in water is called micelle.

97. When soap is dissolved in water, if forms a colloidal suspension is which the soap molecules cluster together to form spherical micelles.

Soap has one polar end (The end with - C - O carboxy) and one non-polar end (The end with hydrocarbon chain)


99. The polar end is hydrophilic in nature and this end is attracted towards water. The non-polar end is hydrophobic in nature and it is attracted towards grease or oil the cloth, but not attracted towards water.

100. When soap is dissolved in water, its hydro phobic ends attach themselves to dirt and remove it from the cloth.


Conceptual flow chart:



1) CH3 - CH2 - CH- CH2 - CH3       n - Pentane


1) CH3 - CH = CH - CH = CH2         1, 3 - Pentadiene (or)
                                                                Pent - 1, 3 - diene

1) CH3 - C  C - CH3           2 - Butyne
2) CH  C - CH2 - CH3        1 - Butyne


Alcohols (R - OH) Alkanols:
1) CH3 - CH2 - CH2OH                     1 - Propanol (or) Propan - 1 - ol

3) CH2 = CH -OH                               Eth - 1 - ene - 1 - ol (or) Ethenol
4) CH3 - CH = CH - CH2 - OH         But - 2 - ene - 1 - ol
       5      4     3       2        1
5) CH  C - CH = CH - CH2 - OH    Pent - 2 - ene - 4 - yne - 1 - ol


Aldehydes (R - CHO Alkanal):
1) H - CHO Methanal
2) CH3 - CHO Ethanal

Ketones (R - CO - R Alkanone):
1) CH3 - CO - CH2 - CH3                        2 - Butanone
2) CH3 - CO - CH2 - CO - CH3              Pent - 2, 4 - dione
        4       3        2        1
3) CH3 - CO - CH2 -CHO                       3 - oxo - butanol


Carboxylic acids (R - COOH Alkanoic acid):
1) HCOOH                                                 Methanoic acid
2) CH3 -COOH                                         Ethanoic acid
3) HOOC - CH2 - CH2 - COOH             Butane - 1, 4 - dioic acid

2) H - COOCH3                                      Methyl Methanoate



1) CH3 -  NH2     Methanamine

1) CH3 - NH - CH3    N - Methyl amino methane

1) CH3 - CH2 - CH2 - CH- CH3                n - Pentane

Compound - Structural  Formulae

Posted Date : 17-11-2020

గమనిక : ప్రతిభ.ఈనాడు.నెట్‌లో కనిపించే వ్యాపార ప్రకటనలు వివిధ దేశాల్లోని వ్యాపారులు, సంస్థల నుంచి వస్తాయి. మరి కొన్ని ప్రకటనలు పాఠకుల అభిరుచి మేరకు కృత్రిమ మేధస్సు సాంకేతికత సాయంతో ప్రదర్శితమవుతుంటాయి. ఆ ప్రకటనల్లోని ఉత్పత్తులను లేదా సేవలను పాఠకులు స్వయంగా విచారించుకొని, జాగ్రత్తగా పరిశీలించి కొనుక్కోవాలి లేదా వినియోగించుకోవాలి. వాటి నాణ్యత లేదా లోపాలతో ఈనాడు యాజమాన్యానికి ఎలాంటి సంబంధం లేదు. ఈ విషయంలో ఉత్తర ప్రత్యుత్తరాలకు, ఈ-మెయిల్స్ కి, ఇంకా ఇతర రూపాల్లో సమాచార మార్పిడికి తావు లేదు. ఫిర్యాదులు స్వీకరించడం కుదరదు. పాఠకులు గమనించి, సహకరించాలని మనవి.

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